Deaerating water



July 5,1927. 1,634,776

, s. H. GIBSON l DEAERATING WATER Filed Sept. 18. 1920 2 Sheets-Sheet lINVENTOR.

w20 ATTORNEY G. H. GIBSON DEAERATING WATER Filed Sept. 18. 1920 2Sheets-Sheet 2 Ugly/W 5./

ud ATTORNEY Patented July 5, 1927.

UNITED STATES PATENT OFFICE.

GEORGE H. GIBSON', OF MONTCLAIR, NEN JERSEY, ASSIGNOR TO COCHRANECORPORA- TION, 0F PHILADELPHIA, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA.

DEAERATING Vf ATE R.

Application filed September 18, 1920.

The general object of the present invention is to provide a simple andeffective method of and apparatus for heating water and freeing it fromair dissolved in it. The invention was primarily devised for use inpreheating boiler feed water where the water is heated in part by beingpassed through an economizer or Water heater receiving heat from theflue gases issuing from the boiler furnace. The primary purpose ofremoving the air dissolved in the water is to reduce the corrosiveeffect of the water, which is especially deleterious when, as isfrequently desirable, the tubes of the economizer are made of steel.

In a preferred mode of carrying out the invention, the air is removedfrom the water by passing the water through an ordinary feed waterheater operated so as to heat the water passing through it to atemperature in the neighborhood of and preferably slightly above 212.Suitable provisions are made for discharging the liberated air withoutpermitting the escape of appreciable quantities of steam from theheater. The water discharged from the heater at a temperature of 212 orabove is too hot to be passed into the economizer if the most effectiveuse ofthe latter is desired. To cool the water down before passing it tothe economizer and thereby increase the economizer eiiiciency while atthe same time avoiding any waste of heat, I provide a heat exchanger inthe path of the water from the open feed water heater to the economizer,and utilize this heat exchanger as a means for preliminarily heating thecold water which also traverses the heat exchanger in passing to theopen feed water heater. The heat thus imparted to the water entering thefeed water heater reduces the amount of steam which must be utilized inthe heater.

In a modified mode of carrying out the invention, I heat the water inthe open feed water heater somewhat higher than in the mode firstdescribed by maintaining a steam pressure in the steam space of theheater a few pounds above that of the atmosphere and pass the water fromthe heater into a spray chamber in which a pressure approximately thatof the atmosphere is maintained. In carrying out the invention in thismanner I make provisions for discharging liberated air both from theopen feed water heater and from the spray chamber. From the Serial No.41 1,232.

spray chamber the air freed water may be passed to a heat exchanger andthence to an economizer, as in the mode of operation first described.

The various features of novelty which characterize my invention arepointed out in particularity in the claims annexed to and forming a partof this specification. For a better understanding of my invention,however, and the advantages possessed by it, reference should be had tothe accompanying drawings and descriptive matter in which I haveillustrated and described preferred embodiments of my invention.

Of the drawings:

Fig. l is a .somewhat diagrammatic representation of a boiler plantcomprising a preferred form of apparatus for use in carrying out thefirst above described mode of operation; and

Fig. 2 is a diagrammatic representation of apparatus for carrying outthe second above described mode of operation.

In the drawings and referring first to the construction shown in Fig. l,A represents an open feed water heater provided at its upper end with atrough A1 receiving the water to be heated which is supplied by a pipeB. The water overflowing from the trough A1 falls on to splash trays orbaffles 85 C. The supply of water to the heater is regulated by valve B1in the supply pipe B which is controlled by a fioat B2 so as to maintainthe water level in the heating chamber approximately at the level of theline A5. A2 represents a. vent pipe from the heater, and A3 a backpressure valve therein, set to open and permit the escape of excesssteam when the pressure in the heater exceeds the predetermined maximumpres- L sure desired. D represents an exhaust steam 4 supply pipethrough which exhaust steam passes into the heating chamber through theusual oil and water separator E, the drip from which passes into adischarge trap El, which may also serve to take the overflow of waterfrom the heater when the water level rises too high in the heater. In sofar as above described the open feed water heater shown is of well knowntype.

In accordance with the present invention I preferably employ anauxiliary heating device L in the heating chamber and onto which thewater from the trays E splashes and over which it Hows in film-likestreams.

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' shown thisy auxiliary heater is in the torni o't' a hollow tra)T orbox. preferablyv 'l'orntetl with Isloping' sit'les, and receiving;` liresteani or exhaust steam at a pressure above that in the steain spare otthe heater, through a supw ply pipe lf. Tater ot Condensation vtermine'in the heater L may be withdrawn troni the latte' and, passed into theheater A by the tlrain pipe l? and a suitable steam trap M. rThe airylibera'lerl 'troni the water in the heater pasf out et the latterthrough the inelineil pipe G1 into a Cooler G, whieh, as shown. is inthe 'torni oit a clruin surroundine the eoltl water supply pipe BA. Thetlruin G' proricletl with an air outlet G2, 'llow throne-h which iscontrolled by an auto inatie air valve Gt". which rnai7 well be ol the srlphou or other known theri'nostatie type and which permits the escapeof the air hut prevents the escape ot steain.

'lhe 'ater flowing to the heater through the pipe l?) is passed througha heatl e2:- ehangler H which is also trarersetl by the water leavingthe heater through the outlet llt. As shown this heat exchanger is oilthe tubular type with the pipe B forming the outlet troni the inter-tubespace ot the heat exchanger. lllater is supplied to the intel'- tuhespare hy the eoltl water supply pipe BA. The water entering' the heatexchanger il'roin the heater outlet At, 'flows through the tubes ll oflthe heat exchanger and then passes through pipe I and pump J to theeeououlizer l, and atter heine; heated in the latter, is passed into theboiler l) through the eeononiizer water outlet K1.

'Vhe exact teniperatures prevailing iu (litterent portions ot theapparatus shown uia \T vary ot rourse with the eonrlitions oit use, butlA will say by wayY ot example that in a typical plant the apparatusmayY well he so proportioned aurl operaleil that with the water passino'to the air cooler fl through the eoltl water supply pipe BA at' t300ll., the temperature oit the water leaving;t the Cooler :unl passing''troni it to the heat exchanger ll will be T0 F., the ten'iperaturo ofthe water learinn' the heater through the outlett will he 215 llt.. anrlthe temperature et water passing' `l'roui the heat exehaneer to theeeonoinizer li will be 150 F.

ln such a plant as that just tleseribetl` the preasure in the sleauispare ol the heater ,Pl will he ot' ronnie. approximately the pretssul'eoit Saturated steain at the water tlierehargo temperliture of S2159. lupraetiee but a sinall aniounl ot the heat imparted to the water in itspasaala'e lhroupjh the healer will be rle riretl troni the auxiliaryheater L. the priniarjv .lunetiou ot which is merel); to subjert the'ater [lowing over it lo an enere'etieboilM ina' aetion with aronsequent lilieration ol' air still contained in the water. On accounto t the relatively lare'e surface ot the heating device and theFilm-like condition of the reali-,rre

water flowingr over il., this'y boiling' artion can be ohtaiuell with arelatirel7 sniall expenditure ot heat. lu nornlal operation the air andother nasen liberated itroni the water in the heater. itlow through theoutlet tl'l into the Cooler tl whieh serres as a eouileuser torcondensing' the Steani rnixell with the enterine; air autl gases. The,resultant lwater o'li Condensation is pre'lerably returnerl to theheater and. in the arranegeinenti shown. may tlow baelc into the heaterthrough the inelinetl pipe eonneetion G1. Arlrantaeeously thiseonneetion G1 is arrangi'erl to eause the water to tlow over seine ofthe lower trays C oit the heater A.

lith the apparatus o't' Fie'. ft. it is possible to retluee the air orair anfl earhou rlioxitle Content in the water leaving: the heater .ltrto an amount: not exeeetlinej .2 enbie centimeter per liter. althoughthe water enteringl the heater nia)T anll 'trenuentl'if will. inpraetiee, eontain inueh as 30 eubie eenlinieters 'per liter. and thefater may contain impurities whit-h will result in the lilieration oliConsiderable quantities ot carbon rlioxitle troni the water as it passesthrough the heater. TVater (loes not have a. troublesome Corrosiveetteet because ot air flissolverl in it. unless the air is present inamounts 4jreater than ,2 eubie centimeter per liter.

The nioililietl 'torni ot a pparatus .shown in Figi'. Q tlill'ers tronithat. shown in 'Fin'. Il priniarilrY in the insertion ot a` sprayvehaiuber O between the water outlet from the heater A anrl the heatexehanpjer H. in the provision ot a cooler Gilt similar to the cooler ttand eooletl by the water passing' tlu'orurh the pipe B to the heaterrtl, au l in the omission ot' the heater l). 'Vlie eooler Grt is ron--neetetl hy a pipe (lm to tlu` spra)7 tank t) aml serres li'lte theronnertion (ll to the eooler G as a eonrluit' 'l'or passlne' air :unlwater y*apor into the cooler Gift :troni the spray ehalnber (L aiul ttorreturningl water eolulensation to the latter. 'The water pasaes i'roin'the healer A. into the upper enll o l the spray chamber O through apipe itt eonneetetl within the sprayv rhaluber (l to a spray heall orrose O1. The l eight nl' water level in the Spray chamber O isreeulatell bjr a lloat. Controlling a 'valve ,/"i" iu the water rontlnitA4". The sprayY rhaiuber (il is prorilleil with a pressure limiting;rent rmlnerliou tl provided with a bartv pressure ralre tt" nel; lo openwhen the gnessure in lhe apra;y rllaiuher t) reaehea a tleeiretlinartiuuun therein which ordinarily about that olv the Muur-Sphere.

lu the operation ot' the appziiratus .shown in Fig'. il. the hart'pressure valve n" slionltl he sel. and the slealn nnppljr lo the healerA so regulated that a Vpresaure a lew pounth: above that ot theatmosphere ia nlaintaineil in the steani spare ol the heater A. lnronsequenee the water passing into the sprav chamber A will he at atemperature corre@ lll@ llltl lllfll lill) lill) sponding to the steampressure in the heater A, say at 220O F. if the back pressure in theheater A is about three pounds. The apparatus is operated to maintain asteam pressure in the spray chamber O approximately that of theatmosphere, and in consequence as the water is sprayed into the steamspace of the chamber O there is an appreciable generation of steam and aliberation of practically all air and gas not liberated from the waterin the heater A. The air thus liberated in the chamber O passes intoIthe cooler GA and is discharged from the latter through the air valve G3in the outlet G2. rllhe heat of evaporation contained in the steampassing` into the cooler GA through the connection G10 is used inheating up the water passing through the pipe B.

It will be obvious to those skilled in the art that the methods ofoperation, and the apparatus required for carrying out the operationsdescribed are simple' and effective and do not require special skill orcare on the part of the attendant. The invention is well adapted for usein handling relatively large quantities of water, and is economical inthe consumption of heat, practically no heat being lost in the operationexcept such as results from radiation losses which, with properlyconstructed and arranged apparatus, will be small.

The deaeration of the water is eected by the consumption of a relativelyand desirably small amount of steam, which, especially in many modernplants in which the supply of available exhaust steam is restricted, isdesirable to avoid lowering` the plant efficiency. 'Vith the type ofapparatus shown in F ig. 2 it is possible, though I do not consider itgenerally desirable, to omit the cooler G and release all the air in thespray chamber O.

YVhile in accordance with the provisions of the statutes l haveillustrated and described the best form of my invention now known to me,it will be apparent to those skilled in the art that changes may be madein the form of the method and apparatus described without departing fromthe spirit of my invention as set forth in the annexed claims.

Having now described my invention, what l claim as new and desire tosecure by Letters Patent, is:

l. The continuous method of treating aircontaining water which consistsiu heating the water to a t nperature above 212o F. to liberate air fromthewater and then cooling the water rto a temperature substantiallybelow 212(l'. by transferringheat from it to the aircontaining.waterbei-ng heated.

2. The method of eiiiciently utilizing an economiz'er in preheatingboiler feed water containing air whichrconsists Yin first heating thewater to a temperature, above 212O F. and then cooling the water toaktemperature substantially below 212o F. by transferring heat from thehotvair 4freed water to the water being heated and passingI,the,.cOOl/Cl vair freed water into the economizer.

3. Water heating and treating apparatus comprising in combination anopen water heater, provided with an outlet for the escape of air, andmeans for passing water into and withdrawing itfrom said heaterincluding a heat exchanger in which heat is transferred from the waterwithdrawn from the heater to the water passing into the heater.

it. Water heating and treating apparatus comprising in combination anopen water heater, a cooler provided with an air outlet, a heatexchanger, connections for passing air and vapor to the cooler from theheater and for returning water of condensation to the latter, andconnections for passing the water to be heated successively through thecooler, heat exchanger, heater and back through the heat exchanger.

5. Apparatus for removing gases from liquids comprising a vessel havingan upper part constituting a direct contact condenser and a lower partconstituting a surface heater, means for introducing the liquid to beheated into the upper part, means for causing said liquid to fall in ashower from the upper part on to the heated surface, said meansextending from one side of the vessel to the other, and an outlet forair in the upper part, whereby the incoming liquid operates by directcontact to condense liquid vapor rising` with the air from the heatedsurface and permits the air to pass off to the air outlet.

6. A process of deaerating water which consists in dropping the water tobe deaerated on a surface heated to a temperature sufficiently higherthan said water to liberate the gases and causing said gases to passthrough the dropping water to remove any water vapor in the gases, andthereafter removing the gases.

7. Apparatus for removing gases from liquids comprising a vessel havingan upper part constituting a direct contact condenser and a lower partconstituting a surface heater, means for introducing the liquid to beheated into the upper part, means for causing said liquid to fall in ashower from the upper part on to the heated surface, said meansextending from one side of the vessel to the other, an outlet for air inthe upper part, whereby the incoming liquid operates by direct contactto condense liquid vapor rising with the air fromv the heated surfaceand permits the air to pass off to the air outlet, and means forsupplying steam to the upper part of said vessel at a temperatureintermediate the temperature of the liquid introduced and thetemperature of the heated surface.

8. Apparatus for the removal of gases iliroui liquidi-4 coiuprisiug avessel, means for introducing liquid into the vessel in a fallingshower, an exposed heating surface Within said vessel sutlieient tocllect ebullition of the liquid at the temperature and pressure existingin the vessel, said surface being arrangetfl beneath the falling` showerand upon which surface the liquid is showered and is ehullatcd. and aconnection to the vessel for the introduction otI a heating medium froman outside source into direct contact With the liquid Yfalling throughthe vessel.

5l. A pparatus tor the removal of gases liront liquids, comprising avessel, lne-ans tor introducing liquid into said vessel, in a talliugshouer, an exposed steam heated surface within said vessel, said surfacebeing arranged beneath the falling shower and sutlcient tio etiiectebullition et the liquid at the temperature and pressure existing in thevessel upon which suriace said liquid is showered and is ebullated, anda connection to the vessel for the introduction oit steam from anoutside source into direct Contact with the liquid falling through thevessel.

lO. Apparatus for the removal ot gases trein liquids comprising aressel, a heating surface within said ressel sutiicient to effectehullition ot' the liquid at the temperature existing in the vessel,means for causing the essere@ liquid to tall in a divided eoiidition outio said surface and a connection to the Vessel lor the introductionoi.l a heating medium 'from an outside source 'into direct Contact withthe liquid within the Vessel.

ll. Apparatus :tor the removal oit gases troni liquids comprising avessel, a steam heated surtace within said vessel suilcient to effectehullition ot the liquid at the teinperatuie existing in the vessel,means 'for causing the liquid to it'all in a divided c011- dilion on tosaid surface and a connection t0 the vessel for the introduction o steamfrom an outside source into direct Contact with the liquid within thevessel.

l2. Apparatus :tor the removal of gases troni liquids conqn'ising aVessel, a steam heated surface Within said Vessel sulftcient to etieetehullition ot the liquid at the telnikwratui-e existing in the Vessel,means for causing the liquid to tall in a divided c0ndition on to saidsurface and a connection to the vessel tor the introduction of steamtroia an outside source into direct Contact with the :tf-killing liquidWithin the Vessel.

tigned at New York, in the county of New Yori; and State et New York,this 14th da)Y of September, A. D. 1920.

GEORGE H. GIBSON.

